Inertia-actuated switch



July 27,1948. A. c. CHAMBERS INERTIA-ACTUATED swncn Original Filed Aug.15, 1939 INVHVTOR ALLA/v CZ CHAMBERS l C-CL.7 (a:

Patented July 27, 1948 UNITED STATES PATENT OFFICE lNERTIA-AGTUATEDSWITCH Allan 0. Chambers, South Bend, Ind., assignor to Bendix AviationCorporation, South Bend, lnd., a corporation of Delaware 3 Claims. (Cl.202-52) An object of my invention is to provide a simple and easilyserviced spring and inertia operated switch operating mechanism, saidmechanism being adapted for use as a part of means for controlling theoperation of the brakes of a motor vehicle.

This invention relates to switch mechanism adapted for use in the powerplant of an automotive vehicle, particularly a power plant including abrake controlling no-roll mechanism such as that disclosed in my PatentNo. 2,391,129, dated December 18, 1945. The instant application is adivision of the latter patent and said patent is a division of my PatentNo. 2,297,692, dated October 6, 1942.

The most important object of my invention is to provide a simple,compact and easily serviced switch mechanism including inertia operatedmeans for controlling the switch opening movement of a movable contactof the mechanism.

The above and other objects and features of the invention will appearmore fully hereinafter from a consideration of the following descriptiontaken in connection with the accompanying drawing wherein one embodimentof the invention is illustrated by way of example.

This drawing is a sectional view disclosing the details of a preferredembodiment of the inertia operated breaker switch mechanism constitutingmy invention.

Describing this switch mechanism it will be assumed that the same isincorporated in the brake controlling no-roll mechanism of an automotivevehicle and that said vehicle is headed to the left with respect to thefigure of the drawing.

Referring now to the drawing a lever 220, weighted at one of its ends bya pendulum weight 22l, is pivotally mounted at its other end upon a pin222, mounted in a casing 224. A multi-diametered pin 226, slidablymounted at one end in a boss 228 extending from the casing and extendingthrough an opening in the shank of the lever 220, is urged to the rightby a spring 229 to force an electrical contact 230 into engagement withan electrical contact 232 said contacts being secured respectively tothe pin 225 and to a pin 2 extending through a bushing 236 mounted inthe casing 224.

The contact 230 is preferably electrically grounded by the grounding ofthe casing 224. When the vehicle is at rest on level ground or on anincline the lever 220 is spaced from a portion '23. constituting a partof the pin 226; ac-

cordingly at this time the spring 22! serves to maintain the contacts230 and 232 in engagement. Should the vehicle be decelerated at or abovea predetermined rate or brought to a stop on a relatively steep declinethe relative positions of the lever 220 and casing 224 are then such asto effect a compression of the spring 229 and a consequent separation ofthe contacts 230 and 232. A stop 240, adjustably mounted in the casing,serves to prevent the lever from contacting the portion 238 should thevehicle be jerked when starting the same in motion accordingly this stopserves to prevent the lever from damaging the contacts.

There is thus provided a relatively simple and compact switch mechanismwell adapted for use in a no-roll brake mechanism of an automotivevehicle; for with the mechanism of my invention the switch 230, 232 isnormally closed to render the no-roll mechanism operative; however saidswitch is automatically opened by the movement of the interior operatedweight 22l when the vehicle is decelerated at or above a certaincritical factor. Thus with the switch mechanism of my inventionincorporated in a no-roll brake holding mechanism said mechanism isautomatically disabled either when the car is positioned on a relativelysteep decline or when the brakes are applied to effectall normaloperations of decelerating the car to a stop. At all other times theswitch 230, 232 is closed to render the no-roll mechanism operative.

However, it is apparent that the switch mechanism of my invention may beemployed as a control means in any type of electrically controlledmechanism wherein an electrical circuit is to be broken with theoperation of an inertia operated member.

I claim:

1. A switch and operating means therefor adapted for use on anautomotive vehicle comprising a hollow casing securable to the chassisof the vehicle, a pin mounted in one of the side walls of said casingand extending therein, a lever pivotally mounted at one of its ends uponsaid pin, a weight secured to the other end of said lever,'a stopadjustably mounted in said casing and contactable by said weight, a pinslidably mounted in the casing, another pin, serving as an electricalconductor, fixedly mounted in said casing opposite said slidable pin, anelectrical contact secured to one end of said latter pin, an electricalcontact secured to the end of said fixed pin, and a spring housed withinthe casing, said spring serving to move said movable pin so as tonormally bring said contacts into 3 engagement with each other. theparts of the switch mechanism being so constructed and arranged that thelever member contacts a portion of said movable pin to move the latterwhen the casing is being decelerated at a predetermined rate and thusseparate the electrical contacts.

2. A switch and operating means therefor comprising an electricallygrounded casing, a flxed contact mounted in said casing, a movablecontact positioned opposite said fixed contact and also mounted in saidcasing. a switch operating lever member pivotally mounted within saidcasing said member being provided with an opening through which extendsthe movable switch member, a portion 0! the latter member beingcontactable by the lever member, a weight secured to one end of thelever member to make of said member a pendulum and a spring mountedwithin the casing and normally serving to force the aforementionedcontacts into engagement with each other.

- 3. A switch and operating means therefor comprising an electricallygrounded casing, a fixed contact mounted in said casing, a movablecontact positioned opposite said fixed contact and also mounted in saidcasing, a switch operating lever member pivotally mounted within saidcasing, said member being provided with mentioned contacts intoengagement with each other.

ALLAN c. CHAMBERS.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 1,256,134 Joeck Feb. 12, 19182,035,087 Logan Mar. 24, 1936 2,048,866 Hunt July 28, 1936 2,391,129Chambers Dec. 18, 1945

